Merc 190E cuts out once hot

I have a 190E 1988 2.6 petrol injection mercedes which has been in my local garage for months now and they cant figure out the problem, though they are not familiar with this car.  The car starts fine, but once she gets hot just cuts out.... can anyone give me any ideas as to what maybe causing this....
thanks

Could be several different things,faulty coolant temp  or air temp sensor would both be possible.When it cools down,does it start again?
http://www.autohausaz.com/search/product.aspx?sid=mae2b155hls2effi2fnfkg55&makeid=800016@Mercedes&modelid=1192665@190E&year=1988&cid=25@Ignition%20Parts&gid=7196@Crankshaft%20Position%20Sensor
replace the rear one listed it is on the bell housing of the transmission..Cheap fixes and bad cps will display the hot stop you point out.If they cant fix it after all this time,get to a new shop.
ohlord